ScalingStacks

Proposition 4.5 . [05AI]

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Proposition 4.5.

The measure defined above has the following properties:

  1. i)

    c1​(𝔏1)βˆ§β€¦βˆ§c1​(𝔏n)c_{1}(\mathfrak{L}_{1})\wedge...\wedge c_{1}(\mathfrak{L}_{n}) is a discrete measure (i.e. of the form βˆ‘x∈SΞ»x​δx\sum_{x\in S}\lambda_{x}\delta_{x} with SβŠ†XS\subseteq X a closed discrete subset, Ξ»xβˆˆβ„\lambda_{x}\in\mathbb{R} and Ξ΄x\delta_{x} the Dirac-measure at xx) whose support is contained in the relative interior of XX over KK (in the sense of [Ber93, 1.5]).

  2. ii)

    c1​(𝔏1)βˆ§β€¦βˆ§c1​(𝔏n)c_{1}(\mathfrak{L}_{1})\wedge...\wedge c_{1}(\mathfrak{L}_{n}) is multilinear and symmetric in 𝔏1,…,𝔏n\mathfrak{L}_{1},...,\mathfrak{L}_{n}.

  3. iii)

    Let Ο†:𝔛′→𝔛\varphi:\mathfrak{X}^{\prime}\rightarrow\mathfrak{X} be a proper morphism of admissible formal schemes over K∘K^{\circ} with irreducible and reduced generic fibres of dimension nn such that the induced morphism on the generic fibres is surjective. Then for formal line bundles 𝔏1,…,𝔏n\mathfrak{L}_{1},...,\mathfrak{L}_{n} on 𝔛\mathfrak{X} we have

    (Ο†an)βˆ—β€‹(c1​(Ο†βˆ—β€‹π”1)βˆ§β€¦βˆ§c1​(Ο†βˆ—β€‹π”n))=deg⁑(Ο†an)​c1​(𝔏1)βˆ§β€¦βˆ§c1​(𝔏n).(\varphi^{\textup{an}})_{\ast}\left(c_{1}(\varphi^{\ast}\mathfrak{L}_{1})\wedge...\wedge c_{1}(\varphi^{\ast}\mathfrak{L}_{n})\right)=\Deg(\varphi^{\textup{an}})c_{1}(\mathfrak{L}_{1})\wedge...\wedge c_{1}(\mathfrak{L}_{n}).

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